Scientists from the Spanish National Cancer Research Centre (CNIO), University of Valencia, and IMDEA Food from Madrid, tried to increase the global antioxidant capacity of the cells, rather than just one or a few antioxidant enzymes.
To achieve this, researchers have focused on increasing the levels of NADPH, a simple molecule that is important in antioxidant reactions.
The researchers used a genetic approach to increase NADPH levels. They generated transgenic mice with an increased glucose-6-phosphate dehydrogenase (G6PD) expression in their bodies, one of the important enzymes for production of NADPH.
When researchers analysed long-lived transgenic animals, they found that their levels of oxidative damage were lower than in non-transgenic animals of the same age.
More From This Section
They also studied the propensity of these animals to develop cancer and found no difference, suggesting that enhancing G6PD activity does not have an important effect on the development of cancer.
When researchers measured the ageing process in the transgenic mice, they found that the animals with a high G6PD expression and high levels of NADPH, delayed their ageing, metabolised sugar better and presented better movement coordination as they aged.
"This increased longevity, although modest, is striking taking into account that until now attempts to increase longevity by manipulating individual antioxidant enzymes had failed," said Pablo Fernandez-Marcos, from IMDEA Food.
Perhaps the key is that the researchers enhanced all antioxidant enzymes in a comprehensive manner.
"Compared to the traditional approach of administering antioxidants that react directly with oxygen, we have stimulated all the cell's natural antioxidant mechanisms by raising G6PD levels, and its by-product, NADPH," said Mari Carmen Gomez-Cabrera, from the University of Valencia.
More specifically, vitamin B3 and its derivatives are responsible for the synthesis of NADPH precursors and are suitable candidates for future studies.
The study was published in the journal Nature Communications.